<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        .div{
            display: grid;
            grid-template-columns: 1fr 1fr 1fr;
            /* grid-template-rows: 100px 100px 100px; */
            width: 700px;
            height: 700px;
            border: 1px solid rgb(0, 255, 34);
        }
        .div>div{
            border: 1px solid red;
        }
    </style>
</head>
<body>
    <div class="div">
        <div></div>
        <div></div>
        <div></div>
        <div></div>
        <div></div>
        <div></div>
        <div></div>
        <div></div>
        <div></div>
    </div>
</body>
</html>